Association between Tooth Agenesis and Skeletal Malocclusions

Abstract

ObjectivesThe aim of this study was to evaluate the association between tooth agenesis and skeletal malocclusions in Brazilian non-syndromic orthodontic patients.Material and MethodsPretreatment orthodontic records of 348 patients of both genders and with various skeletal malocclusions were examined. Tooth agenesis was evaluated in panoramic radiographs. Angular measurements were taken from lateral cephalometric radiographs to classify the patient’s malocclusion as skeletal Class I, Class II and Class III. Subjects were divided into 2 groups, “with tooth agenesis” and “without tooth agenesis”. Chi-square or Fisher exact test was used to compare categorical data. ANOVA with Tukey’s post-test was used for means comparisons. An alpha of 5% was established. ResultsFrom 348 analysed patients, 28 presented tooth agenesis. There was no difference between genders (P = 0.27) nor mean age (P = 0.16). The most prevalent skeletal malocclusion was Class I (63.11%), followed by Class II (25.94%), and Class III (10.95%). The mean of congenitally missing teeth was 1.3 (SD 0.13). Thirteen subjects had premolar agenesis, 13 upper lateral incisor agenesis, 4 lower incisor agenesis and 2 molars agenesis. The group with tooth agenesis presented A point-nasion-B point (ANB) angle smaller (1.66 [SD 2.52]) than the group without tooth agenesis (2.86 [SD 2.49]) (P = 0.01). ANB angle had a negative correlation with the number of congenitally missing teeth (P = 0.039; r = -0.39).ConclusionsTooth agenesis is associated with a smaller A point-nasion-B point angle and is negatively correlated with the number of congenitally missing teeth.

Prevalence and patterns of tooth agenesis among malocclusion classes in a Japanese orthodontic population

“…While this is consistent with the findings of some studies [10,12], other studies have indicated that Class III patients have a higher prevalence of agenesis of teeth other than the M3s than their patients with TA [9]. Costa et al [11] have found Class III malocclusions to be significantly associated with the agenesis of the premolars, Celikoglu et al [15] found this to be the case with the MxI2s.…”

“…Several studies have found no significant differences in the prevalence of TA among different sagittal jaw relationship groups [10][11][12]. Others have reported that agenesis of the M3s depends on sagittal skeletal malocclusion [5] and that TA is significantly less common in skeletal Class II malocclusions [13].…”

“…Some studies have verified that Class III and Class II patients had a higher [9] and a lower [13] prevalence of agenesis of teeth other than the M3s, respectively. Studies in Caucasian [14] and Bra-zilian orthodontic populations [11] have noted that the A point, nasion, and B point (ANB) angle significantly decreases with an increasing number of CMT, excluding M3s. Very few studies have found that skeletal Class III malocclusions exhibit a high prevalence of agenesis of the MxI2s [15] and the premolars [11].…”

“…Studies in Caucasian [14] and Bra-zilian orthodontic populations [11] have noted that the A point, nasion, and B point (ANB) angle significantly decreases with an increasing number of CMT, excluding M3s. Very few studies have found that skeletal Class III malocclusions exhibit a high prevalence of agenesis of the MxI2s [15] and the premolars [11]. These studies did not investigate, in detail, the distribution or pattern of TA among different skeletal malocclusions.…”

Associação entre polimorfismos genéticos em RANK, RANKL e OPG com alterações nas dimensões craniofaciais

“…Por outro lado, a cefalometria é o método que estuda as dimensões do crânio e da face, sendo amplamente utilizada nos estudos em Ortodontia que visam analisar as variações individuais nas dimensões maxilares e mandibulares (Li et al, 2010;Costa et al, 2017;Cruz et al, 2017).…”